mirror of
https://github.com/FEX-Emu/linux.git
synced 2024-12-13 11:51:32 +00:00
MODSIGN: Use PKCS#7 messages as module signatures
Move to using PKCS#7 messages as module signatures because:
(1) We have to be able to support the use of X.509 certificates that don't
have a subjKeyId set. We're currently relying on this to look up the
X.509 certificate in the trusted keyring list.
(2) PKCS#7 message signed information blocks have a field that supplies the
data required to match with the X.509 certificate that signed it.
(3) The PKCS#7 certificate carries fields that specify the digest algorithm
used to generate the signature in a standardised way and the X.509
certificates specify the public key algorithm in a standardised way - so
we don't need our own methods of specifying these.
(4) We now have PKCS#7 message support in the kernel for signed kexec purposes
and we can make use of this.
To make this work, the old sign-file script has been replaced with a program
that needs compiling in a previous patch. The rules to build it are added
here.
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Vivek Goyal <vgoyal@redhat.com>
This commit is contained in:
David Howells
parent
bc1c373dd2
commit
3f1e1bea34
2
Makefile
2
Makefile
@ -873,7 +873,7 @@ ifdef CONFIG_MODULE_SIG_ALL
|
||||
MODSECKEY = ./signing_key.priv
|
||||
MODPUBKEY = ./signing_key.x509
|
||||
export MODPUBKEY
|
||||
mod_sign_cmd = perl $(srctree)/scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODSECKEY) $(MODPUBKEY)
|
||||
mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODSECKEY) $(MODPUBKEY)
|
||||
else
|
||||
mod_sign_cmd = true
|
||||
endif
|
||||
|
||||
@ -1869,6 +1869,7 @@ config MODULE_SIG
|
||||
select ASN1
|
||||
select OID_REGISTRY
|
||||
select X509_CERTIFICATE_PARSER
|
||||
select PKCS7_MESSAGE_PARSER
|
||||
help
|
||||
Check modules for valid signatures upon load: the signature
|
||||
is simply appended to the module. For more information see
|
||||
|
||||
@ -11,10 +11,9 @@
|
||||
|
||||
#include <linux/kernel.h>
|
||||
#include <linux/err.h>
|
||||
#include <crypto/public_key.h>
|
||||
#include <crypto/hash.h>
|
||||
#include <keys/asymmetric-type.h>
|
||||
#include <keys/system_keyring.h>
|
||||
#include <crypto/public_key.h>
|
||||
#include <crypto/pkcs7.h>
|
||||
#include "module-internal.h"
|
||||
|
||||
/*
|
||||
@ -28,157 +27,53 @@
|
||||
* - Information block
|
||||
*/
|
||||
struct module_signature {
|
||||
u8 algo; /* Public-key crypto algorithm [enum pkey_algo] */
|
||||
u8 hash; /* Digest algorithm [enum hash_algo] */
|
||||
u8 id_type; /* Key identifier type [enum pkey_id_type] */
|
||||
u8 signer_len; /* Length of signer's name */
|
||||
u8 key_id_len; /* Length of key identifier */
|
||||
u8 algo; /* Public-key crypto algorithm [0] */
|
||||
u8 hash; /* Digest algorithm [0] */
|
||||
u8 id_type; /* Key identifier type [PKEY_ID_PKCS7] */
|
||||
u8 signer_len; /* Length of signer's name [0] */
|
||||
u8 key_id_len; /* Length of key identifier [0] */
|
||||
u8 __pad[3];
|
||||
__be32 sig_len; /* Length of signature data */
|
||||
};
|
||||
|
||||
/*
|
||||
* Digest the module contents.
|
||||
* Verify a PKCS#7-based signature on a module.
|
||||
*/
|
||||
static struct public_key_signature *mod_make_digest(enum hash_algo hash,
|
||||
const void *mod,
|
||||
unsigned long modlen)
|
||||
static int mod_verify_pkcs7(const void *mod, unsigned long modlen,
|
||||
const void *raw_pkcs7, size_t pkcs7_len)
|
||||
{
|
||||
struct public_key_signature *pks;
|
||||
struct crypto_shash *tfm;
|
||||
struct shash_desc *desc;
|
||||
size_t digest_size, desc_size;
|
||||
struct pkcs7_message *pkcs7;
|
||||
bool trusted;
|
||||
int ret;
|
||||
|
||||
pr_devel("==>%s()\n", __func__);
|
||||
|
||||
/* Allocate the hashing algorithm we're going to need and find out how
|
||||
* big the hash operational data will be.
|
||||
*/
|
||||
tfm = crypto_alloc_shash(hash_algo_name[hash], 0, 0);
|
||||
if (IS_ERR(tfm))
|
||||
return (PTR_ERR(tfm) == -ENOENT) ? ERR_PTR(-ENOPKG) : ERR_CAST(tfm);
|
||||
pkcs7 = pkcs7_parse_message(raw_pkcs7, pkcs7_len);
|
||||
if (IS_ERR(pkcs7))
|
||||
return PTR_ERR(pkcs7);
|
||||
|
||||
desc_size = crypto_shash_descsize(tfm) + sizeof(*desc);
|
||||
digest_size = crypto_shash_digestsize(tfm);
|
||||
/* The data should be detached - so we need to supply it. */
|
||||
if (pkcs7_supply_detached_data(pkcs7, mod, modlen) < 0) {
|
||||
pr_err("PKCS#7 signature with non-detached data\n");
|
||||
ret = -EBADMSG;
|
||||
goto error;
|
||||
}
|
||||
|
||||
/* We allocate the hash operational data storage on the end of our
|
||||
* context data and the digest output buffer on the end of that.
|
||||
*/
|
||||
ret = -ENOMEM;
|
||||
pks = kzalloc(digest_size + sizeof(*pks) + desc_size, GFP_KERNEL);
|
||||
if (!pks)
|
||||
goto error_no_pks;
|
||||
|
||||
pks->pkey_hash_algo = hash;
|
||||
pks->digest = (u8 *)pks + sizeof(*pks) + desc_size;
|
||||
pks->digest_size = digest_size;
|
||||
|
||||
desc = (void *)pks + sizeof(*pks);
|
||||
desc->tfm = tfm;
|
||||
desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP;
|
||||
|
||||
ret = crypto_shash_init(desc);
|
||||
ret = pkcs7_verify(pkcs7);
|
||||
if (ret < 0)
|
||||
goto error;
|
||||
|
||||
ret = crypto_shash_finup(desc, mod, modlen, pks->digest);
|
||||
ret = pkcs7_validate_trust(pkcs7, system_trusted_keyring, &trusted);
|
||||
if (ret < 0)
|
||||
goto error;
|
||||
|
||||
crypto_free_shash(tfm);
|
||||
pr_devel("<==%s() = ok\n", __func__);
|
||||
return pks;
|
||||
if (!trusted) {
|
||||
pr_err("PKCS#7 signature not signed with a trusted key\n");
|
||||
ret = -ENOKEY;
|
||||
}
|
||||
|
||||
error:
|
||||
kfree(pks);
|
||||
error_no_pks:
|
||||
crypto_free_shash(tfm);
|
||||
pkcs7_free_message(pkcs7);
|
||||
pr_devel("<==%s() = %d\n", __func__, ret);
|
||||
return ERR_PTR(ret);
|
||||
}
|
||||
|
||||
/*
|
||||
* Extract an MPI array from the signature data. This represents the actual
|
||||
* signature. Each raw MPI is prefaced by a BE 2-byte value indicating the
|
||||
* size of the MPI in bytes.
|
||||
*
|
||||
* RSA signatures only have one MPI, so currently we only read one.
|
||||
*/
|
||||
static int mod_extract_mpi_array(struct public_key_signature *pks,
|
||||
const void *data, size_t len)
|
||||
{
|
||||
size_t nbytes;
|
||||
MPI mpi;
|
||||
|
||||
if (len < 3)
|
||||
return -EBADMSG;
|
||||
nbytes = ((const u8 *)data)[0] << 8 | ((const u8 *)data)[1];
|
||||
data += 2;
|
||||
len -= 2;
|
||||
if (len != nbytes)
|
||||
return -EBADMSG;
|
||||
|
||||
mpi = mpi_read_raw_data(data, nbytes);
|
||||
if (!mpi)
|
||||
return -ENOMEM;
|
||||
pks->mpi[0] = mpi;
|
||||
pks->nr_mpi = 1;
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Request an asymmetric key.
|
||||
*/
|
||||
static struct key *request_asymmetric_key(const char *signer, size_t signer_len,
|
||||
const u8 *key_id, size_t key_id_len)
|
||||
{
|
||||
key_ref_t key;
|
||||
size_t i;
|
||||
char *id, *q;
|
||||
|
||||
pr_devel("==>%s(,%zu,,%zu)\n", __func__, signer_len, key_id_len);
|
||||
|
||||
/* Construct an identifier. */
|
||||
id = kmalloc(signer_len + 2 + key_id_len * 2 + 1, GFP_KERNEL);
|
||||
if (!id)
|
||||
return ERR_PTR(-ENOKEY);
|
||||
|
||||
memcpy(id, signer, signer_len);
|
||||
|
||||
q = id + signer_len;
|
||||
*q++ = ':';
|
||||
*q++ = ' ';
|
||||
for (i = 0; i < key_id_len; i++) {
|
||||
*q++ = hex_asc[*key_id >> 4];
|
||||
*q++ = hex_asc[*key_id++ & 0x0f];
|
||||
}
|
||||
|
||||
*q = 0;
|
||||
|
||||
pr_debug("Look up: \"%s\"\n", id);
|
||||
|
||||
key = keyring_search(make_key_ref(system_trusted_keyring, 1),
|
||||
&key_type_asymmetric, id);
|
||||
if (IS_ERR(key))
|
||||
pr_warn("Request for unknown module key '%s' err %ld\n",
|
||||
id, PTR_ERR(key));
|
||||
kfree(id);
|
||||
|
||||
if (IS_ERR(key)) {
|
||||
switch (PTR_ERR(key)) {
|
||||
/* Hide some search errors */
|
||||
case -EACCES:
|
||||
case -ENOTDIR:
|
||||
case -EAGAIN:
|
||||
return ERR_PTR(-ENOKEY);
|
||||
default:
|
||||
return ERR_CAST(key);
|
||||
}
|
||||
}
|
||||
|
||||
pr_devel("<==%s() = 0 [%x]\n", __func__, key_serial(key_ref_to_ptr(key)));
|
||||
return key_ref_to_ptr(key);
|
||||
return ret;
|
||||
}
|
||||
|
||||
/*
|
||||
@ -186,12 +81,8 @@ static struct key *request_asymmetric_key(const char *signer, size_t signer_len,
|
||||
*/
|
||||
int mod_verify_sig(const void *mod, unsigned long *_modlen)
|
||||
{
|
||||
struct public_key_signature *pks;
|
||||
struct module_signature ms;
|
||||
struct key *key;
|
||||
const void *sig;
|
||||
size_t modlen = *_modlen, sig_len;
|
||||
int ret;
|
||||
|
||||
pr_devel("==>%s(,%zu)\n", __func__, modlen);
|
||||
|
||||
@ -205,46 +96,23 @@ int mod_verify_sig(const void *mod, unsigned long *_modlen)
|
||||
if (sig_len >= modlen)
|
||||
return -EBADMSG;
|
||||
modlen -= sig_len;
|
||||
if ((size_t)ms.signer_len + ms.key_id_len >= modlen)
|
||||
return -EBADMSG;
|
||||
modlen -= (size_t)ms.signer_len + ms.key_id_len;
|
||||
|
||||
*_modlen = modlen;
|
||||
sig = mod + modlen;
|
||||
|
||||
/* For the moment, only support RSA and X.509 identifiers */
|
||||
if (ms.algo != PKEY_ALGO_RSA ||
|
||||
ms.id_type != PKEY_ID_X509)
|
||||
if (ms.id_type != PKEY_ID_PKCS7) {
|
||||
pr_err("Module is not signed with expected PKCS#7 message\n");
|
||||
return -ENOPKG;
|
||||
|
||||
if (ms.hash >= PKEY_HASH__LAST ||
|
||||
!hash_algo_name[ms.hash])
|
||||
return -ENOPKG;
|
||||
|
||||
key = request_asymmetric_key(sig, ms.signer_len,
|
||||
sig + ms.signer_len, ms.key_id_len);
|
||||
if (IS_ERR(key))
|
||||
return PTR_ERR(key);
|
||||
|
||||
pks = mod_make_digest(ms.hash, mod, modlen);
|
||||
if (IS_ERR(pks)) {
|
||||
ret = PTR_ERR(pks);
|
||||
goto error_put_key;
|
||||
}
|
||||
|
||||
ret = mod_extract_mpi_array(pks, sig + ms.signer_len + ms.key_id_len,
|
||||
sig_len);
|
||||
if (ret < 0)
|
||||
goto error_free_pks;
|
||||
if (ms.algo != 0 ||
|
||||
ms.hash != 0 ||
|
||||
ms.signer_len != 0 ||
|
||||
ms.key_id_len != 0 ||
|
||||
ms.__pad[0] != 0 ||
|
||||
ms.__pad[1] != 0 ||
|
||||
ms.__pad[2] != 0) {
|
||||
pr_err("PKCS#7 signature info has unexpected non-zero params\n");
|
||||
return -EBADMSG;
|
||||
}
|
||||
|
||||
ret = verify_signature(key, pks);
|
||||
pr_devel("verify_signature() = %d\n", ret);
|
||||
|
||||
error_free_pks:
|
||||
mpi_free(pks->rsa.s);
|
||||
kfree(pks);
|
||||
error_put_key:
|
||||
key_put(key);
|
||||
pr_devel("<==%s() = %d\n", __func__, ret);
|
||||
return ret;
|
||||
return mod_verify_pkcs7(mod, modlen, mod + modlen, sig_len);
|
||||
}
|
||||
|
||||
@ -16,9 +16,11 @@ hostprogs-$(CONFIG_VT) += conmakehash
|
||||
hostprogs-$(BUILD_C_RECORDMCOUNT) += recordmcount
|
||||
hostprogs-$(CONFIG_BUILDTIME_EXTABLE_SORT) += sortextable
|
||||
hostprogs-$(CONFIG_ASN1) += asn1_compiler
|
||||
hostprogs-$(CONFIG_MODULE_SIG) += sign-file
|
||||
|
||||
HOSTCFLAGS_sortextable.o = -I$(srctree)/tools/include
|
||||
HOSTCFLAGS_asn1_compiler.o = -I$(srctree)/include
|
||||
HOSTLOADLIBES_sign-file = -lcrypto
|
||||
|
||||
always := $(hostprogs-y) $(hostprogs-m)
|
||||
|
||||
|
||||
@ -1,421 +0,0 @@
|
||||
#!/usr/bin/perl -w
|
||||
#
|
||||
# Sign a module file using the given key.
|
||||
#
|
||||
|
||||
my $USAGE =
|
||||
"Usage: scripts/sign-file [-v] <hash algo> <key> <x509> <module> [<dest>]\n" .
|
||||
" scripts/sign-file [-v] -s <raw sig> <hash algo> <x509> <module> [<dest>]\n";
|
||||
|
||||
use strict;
|
||||
use FileHandle;
|
||||
use IPC::Open2;
|
||||
use Getopt::Std;
|
||||
|
||||
my %opts;
|
||||
getopts('vs:', \%opts) or die $USAGE;
|
||||
my $verbose = $opts{'v'};
|
||||
my $signature_file = $opts{'s'};
|
||||
|
||||
die $USAGE if ($#ARGV > 4);
|
||||
die $USAGE if (!$signature_file && $#ARGV < 3 || $signature_file && $#ARGV < 2);
|
||||
|
||||
my $dgst = shift @ARGV;
|
||||
my $private_key;
|
||||
if (!$signature_file) {
|
||||
$private_key = shift @ARGV;
|
||||
}
|
||||
my $x509 = shift @ARGV;
|
||||
my $module = shift @ARGV;
|
||||
my ($dest, $keep_orig);
|
||||
if (@ARGV) {
|
||||
$dest = $ARGV[0];
|
||||
$keep_orig = 1;
|
||||
} else {
|
||||
$dest = $module . "~";
|
||||
}
|
||||
|
||||
die "Can't read private key\n" if (!$signature_file && !-r $private_key);
|
||||
die "Can't read signature file\n" if ($signature_file && !-r $signature_file);
|
||||
die "Can't read X.509 certificate\n" unless (-r $x509);
|
||||
die "Can't read module\n" unless (-r $module);
|
||||
|
||||
#
|
||||
# Function to read the contents of a file into a variable.
|
||||
#
|
||||
sub read_file($)
|
||||
{
|
||||
my ($file) = @_;
|
||||
my $contents;
|
||||
my $len;
|
||||
|
||||
open(FD, "<$file") || die $file;
|
||||
binmode FD;
|
||||
my @st = stat(FD);
|
||||
die $file if (!@st);
|
||||
$len = read(FD, $contents, $st[7]) || die $file;
|
||||
close(FD) || die $file;
|
||||
die "$file: Wanted length ", $st[7], ", got ", $len, "\n"
|
||||
if ($len != $st[7]);
|
||||
return $contents;
|
||||
}
|
||||
|
||||
###############################################################################
|
||||
#
|
||||
# First of all, we have to parse the X.509 certificate to find certain details
|
||||
# about it.
|
||||
#
|
||||
# We read the DER-encoded X509 certificate and parse it to extract the Subject
|
||||
# name and Subject Key Identifier. Theis provides the data we need to build
|
||||
# the certificate identifier.
|
||||
#
|
||||
# The signer's name part of the identifier is fabricated from the commonName,
|
||||
# the organizationName or the emailAddress components of the X.509 subject
|
||||
# name.
|
||||
#
|
||||
# The subject key ID is used to select which of that signer's certificates
|
||||
# we're intending to use to sign the module.
|
||||
#
|
||||
###############################################################################
|
||||
my $x509_certificate = read_file($x509);
|
||||
|
||||
my $UNIV = 0 << 6;
|
||||
my $APPL = 1 << 6;
|
||||
my $CONT = 2 << 6;
|
||||
my $PRIV = 3 << 6;
|
||||
|
||||
my $CONS = 0x20;
|
||||
|
||||
my $BOOLEAN = 0x01;
|
||||
my $INTEGER = 0x02;
|
||||
my $BIT_STRING = 0x03;
|
||||
my $OCTET_STRING = 0x04;
|
||||
my $NULL = 0x05;
|
||||
my $OBJ_ID = 0x06;
|
||||
my $UTF8String = 0x0c;
|
||||
my $SEQUENCE = 0x10;
|
||||
my $SET = 0x11;
|
||||
my $UTCTime = 0x17;
|
||||
my $GeneralizedTime = 0x18;
|
||||
|
||||
my %OIDs = (
|
||||
pack("CCC", 85, 4, 3) => "commonName",
|
||||
pack("CCC", 85, 4, 6) => "countryName",
|
||||
pack("CCC", 85, 4, 10) => "organizationName",
|
||||
pack("CCC", 85, 4, 11) => "organizationUnitName",
|
||||
pack("CCCCCCCCC", 42, 134, 72, 134, 247, 13, 1, 1, 1) => "rsaEncryption",
|
||||
pack("CCCCCCCCC", 42, 134, 72, 134, 247, 13, 1, 1, 5) => "sha1WithRSAEncryption",
|
||||
pack("CCCCCCCCC", 42, 134, 72, 134, 247, 13, 1, 9, 1) => "emailAddress",
|
||||
pack("CCC", 85, 29, 35) => "authorityKeyIdentifier",
|
||||
pack("CCC", 85, 29, 14) => "subjectKeyIdentifier",
|
||||
pack("CCC", 85, 29, 19) => "basicConstraints"
|
||||
);
|
||||
|
||||
###############################################################################
|
||||
#
|
||||
# Extract an ASN.1 element from a string and return information about it.
|
||||
#
|
||||
###############################################################################
|
||||
sub asn1_extract($$@)
|
||||
{
|
||||
my ($cursor, $expected_tag, $optional) = @_;
|
||||
|
||||
return [ -1 ]
|
||||
if ($cursor->[1] == 0 && $optional);
|
||||
|
||||
die $x509, ": ", $cursor->[0], ": ASN.1 data underrun (elem ", $cursor->[1], ")\n"
|
||||
if ($cursor->[1] < 2);
|
||||
|
||||
my ($tag, $len) = unpack("CC", substr(${$cursor->[2]}, $cursor->[0], 2));
|
||||
|
||||
if ($expected_tag != -1 && $tag != $expected_tag) {
|
||||
return [ -1 ]
|
||||
if ($optional);
|
||||
die $x509, ": ", $cursor->[0], ": ASN.1 unexpected tag (", $tag,
|
||||
" not ", $expected_tag, ")\n";
|
||||
}
|
||||
|
||||
$cursor->[0] += 2;
|
||||
$cursor->[1] -= 2;
|
||||
|
||||
die $x509, ": ", $cursor->[0], ": ASN.1 long tag\n"
|
||||
if (($tag & 0x1f) == 0x1f);
|
||||
die $x509, ": ", $cursor->[0], ": ASN.1 indefinite length\n"
|
||||
if ($len == 0x80);
|
||||
|
||||
if ($len > 0x80) {
|
||||
my $l = $len - 0x80;
|
||||
die $x509, ": ", $cursor->[0], ": ASN.1 data underrun (len len $l)\n"
|
||||
if ($cursor->[1] < $l);
|
||||
|
||||
if ($l == 0x1) {
|
||||
$len = unpack("C", substr(${$cursor->[2]}, $cursor->[0], 1));
|
||||
} elsif ($l == 0x2) {
|
||||
$len = unpack("n", substr(${$cursor->[2]}, $cursor->[0], 2));
|
||||
} elsif ($l == 0x3) {
|
||||
$len = unpack("C", substr(${$cursor->[2]}, $cursor->[0], 1)) << 16;
|
||||
$len = unpack("n", substr(${$cursor->[2]}, $cursor->[0] + 1, 2));
|
||||
} elsif ($l == 0x4) {
|
||||
$len = unpack("N", substr(${$cursor->[2]}, $cursor->[0], 4));
|
||||
} else {
|
||||
die $x509, ": ", $cursor->[0], ": ASN.1 element too long (", $l, ")\n";
|
||||
}
|
||||
|
||||
$cursor->[0] += $l;
|
||||
$cursor->[1] -= $l;
|
||||
}
|
||||
|
||||
die $x509, ": ", $cursor->[0], ": ASN.1 data underrun (", $len, ")\n"
|
||||
if ($cursor->[1] < $len);
|
||||
|
||||
my $ret = [ $tag, [ $cursor->[0], $len, $cursor->[2] ] ];
|
||||
$cursor->[0] += $len;
|
||||
$cursor->[1] -= $len;
|
||||
|
||||
return $ret;
|
||||
}
|
||||
|
||||
###############################################################################
|
||||
#
|
||||
# Retrieve the data referred to by a cursor
|
||||
#
|
||||
###############################################################################
|
||||
sub asn1_retrieve($)
|
||||
{
|
||||
my ($cursor) = @_;
|
||||
my ($offset, $len, $data) = @$cursor;
|
||||
return substr($$data, $offset, $len);
|
||||
}
|
||||
|
||||
###############################################################################
|
||||
#
|
||||
# Roughly parse the X.509 certificate
|
||||
#
|
||||
###############################################################################
|
||||
my $cursor = [ 0, length($x509_certificate), \$x509_certificate ];
|
||||
|
||||
my $cert = asn1_extract($cursor, $UNIV | $CONS | $SEQUENCE);
|
||||
my $tbs = asn1_extract($cert->[1], $UNIV | $CONS | $SEQUENCE);
|
||||
my $version = asn1_extract($tbs->[1], $CONT | $CONS | 0, 1);
|
||||
my $serial_number = asn1_extract($tbs->[1], $UNIV | $INTEGER);
|
||||
my $sig_type = asn1_extract($tbs->[1], $UNIV | $CONS | $SEQUENCE);
|
||||
my $issuer = asn1_extract($tbs->[1], $UNIV | $CONS | $SEQUENCE);
|
||||
my $validity = asn1_extract($tbs->[1], $UNIV | $CONS | $SEQUENCE);
|
||||
my $subject = asn1_extract($tbs->[1], $UNIV | $CONS | $SEQUENCE);
|
||||
my $key = asn1_extract($tbs->[1], $UNIV | $CONS | $SEQUENCE);
|
||||
my $issuer_uid = asn1_extract($tbs->[1], $CONT | $CONS | 1, 1);
|
||||
my $subject_uid = asn1_extract($tbs->[1], $CONT | $CONS | 2, 1);
|
||||
my $extension_list = asn1_extract($tbs->[1], $CONT | $CONS | 3, 1);
|
||||
|
||||
my $subject_key_id = ();
|
||||
my $authority_key_id = ();
|
||||
|
||||
#
|
||||
# Parse the extension list
|
||||
#
|
||||
if ($extension_list->[0] != -1) {
|
||||
my $extensions = asn1_extract($extension_list->[1], $UNIV | $CONS | $SEQUENCE);
|
||||
|
||||
while ($extensions->[1]->[1] > 0) {
|
||||
my $ext = asn1_extract($extensions->[1], $UNIV | $CONS | $SEQUENCE);
|
||||
my $x_oid = asn1_extract($ext->[1], $UNIV | $OBJ_ID);
|
||||
my $x_crit = asn1_extract($ext->[1], $UNIV | $BOOLEAN, 1);
|
||||
my $x_val = asn1_extract($ext->[1], $UNIV | $OCTET_STRING);
|
||||
|
||||
my $raw_oid = asn1_retrieve($x_oid->[1]);
|
||||
next if (!exists($OIDs{$raw_oid}));
|
||||
my $x_type = $OIDs{$raw_oid};
|
||||
|
||||
my $raw_value = asn1_retrieve($x_val->[1]);
|
||||
|
||||
if ($x_type eq "subjectKeyIdentifier") {
|
||||
my $vcursor = [ 0, length($raw_value), \$raw_value ];
|
||||
|
||||
$subject_key_id = asn1_extract($vcursor, $UNIV | $OCTET_STRING);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
###############################################################################
|
||||
#
|
||||
# Determine what we're going to use as the signer's name. In order of
|
||||
# preference, take one of: commonName, organizationName or emailAddress.
|
||||
#
|
||||
###############################################################################
|
||||
my $org = "";
|
||||
my $cn = "";
|
||||
my $email = "";
|
||||
|
||||
while ($subject->[1]->[1] > 0) {
|
||||
my $rdn = asn1_extract($subject->[1], $UNIV | $CONS | $SET);
|
||||
my $attr = asn1_extract($rdn->[1], $UNIV | $CONS | $SEQUENCE);
|
||||
my $n_oid = asn1_extract($attr->[1], $UNIV | $OBJ_ID);
|
||||
my $n_val = asn1_extract($attr->[1], -1);
|
||||
|
||||
my $raw_oid = asn1_retrieve($n_oid->[1]);
|
||||
next if (!exists($OIDs{$raw_oid}));
|
||||
my $n_type = $OIDs{$raw_oid};
|
||||
|
||||
my $raw_value = asn1_retrieve($n_val->[1]);
|
||||
|
||||
if ($n_type eq "organizationName") {
|
||||
$org = $raw_value;
|
||||
} elsif ($n_type eq "commonName") {
|
||||
$cn = $raw_value;
|
||||
} elsif ($n_type eq "emailAddress") {
|
||||
$email = $raw_value;
|
||||
}
|
||||
}
|
||||
|
||||
my $signers_name = $email;
|
||||
|
||||
if ($org && $cn) {
|
||||
# Don't use the organizationName if the commonName repeats it
|
||||
if (length($org) <= length($cn) &&
|
||||
substr($cn, 0, length($org)) eq $org) {
|
||||
$signers_name = $cn;
|
||||
goto got_id_name;
|
||||
}
|
||||
|
||||
# Or a signifcant chunk of it
|
||||
if (length($org) >= 7 &&
|
||||
length($cn) >= 7 &&
|
||||
substr($cn, 0, 7) eq substr($org, 0, 7)) {
|
||||
$signers_name = $cn;
|
||||
goto got_id_name;
|
||||
}
|
||||
|
||||
$signers_name = $org . ": " . $cn;
|
||||
} elsif ($org) {
|
||||
$signers_name = $org;
|
||||
} elsif ($cn) {
|
||||
$signers_name = $cn;
|
||||
}
|
||||
|
||||
got_id_name:
|
||||
|
||||
die $x509, ": ", "X.509: Couldn't find the Subject Key Identifier extension\n"
|
||||
if (!$subject_key_id);
|
||||
|
||||
my $key_identifier = asn1_retrieve($subject_key_id->[1]);
|
||||
|
||||
###############################################################################
|
||||
#
|
||||
# Create and attach the module signature
|
||||
#
|
||||
###############################################################################
|
||||
|
||||
#
|
||||
# Signature parameters
|
||||
#
|
||||
my $algo = 1; # Public-key crypto algorithm: RSA
|
||||
my $hash = 0; # Digest algorithm
|
||||
my $id_type = 1; # Identifier type: X.509
|
||||
|
||||
#
|
||||
# Digest the data
|
||||
#
|
||||
my $prologue;
|
||||
if ($dgst eq "sha1") {
|
||||
$prologue = pack("C*",
|
||||
0x30, 0x21, 0x30, 0x09, 0x06, 0x05,
|
||||
0x2B, 0x0E, 0x03, 0x02, 0x1A,
|
||||
0x05, 0x00, 0x04, 0x14);
|
||||
$hash = 2;
|
||||
} elsif ($dgst eq "sha224") {
|
||||
$prologue = pack("C*",
|
||||
0x30, 0x2d, 0x30, 0x0d, 0x06, 0x09,
|
||||
0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x04,
|
||||
0x05, 0x00, 0x04, 0x1C);
|
||||
$hash = 7;
|
||||
} elsif ($dgst eq "sha256") {
|
||||
$prologue = pack("C*",
|
||||
0x30, 0x31, 0x30, 0x0d, 0x06, 0x09,
|
||||
0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01,
|
||||
0x05, 0x00, 0x04, 0x20);
|
||||
$hash = 4;
|
||||
} elsif ($dgst eq "sha384") {
|
||||
$prologue = pack("C*",
|
||||
0x30, 0x41, 0x30, 0x0d, 0x06, 0x09,
|
||||
0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x02,
|
||||
0x05, 0x00, 0x04, 0x30);
|
||||
$hash = 5;
|
||||
} elsif ($dgst eq "sha512") {
|
||||
$prologue = pack("C*",
|
||||
0x30, 0x51, 0x30, 0x0d, 0x06, 0x09,
|
||||
0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03,
|
||||
0x05, 0x00, 0x04, 0x40);
|
||||
$hash = 6;
|
||||
} else {
|
||||
die "Unknown hash algorithm: $dgst\n";
|
||||
}
|
||||
|
||||
my $signature;
|
||||
if ($signature_file) {
|
||||
$signature = read_file($signature_file);
|
||||
} else {
|
||||
#
|
||||
# Generate the digest and read from openssl's stdout
|
||||
#
|
||||
my $digest;
|
||||
$digest = readpipe("openssl dgst -$dgst -binary $module") || die "openssl dgst";
|
||||
|
||||
#
|
||||
# Generate the binary signature, which will be just the integer that
|
||||
# comprises the signature with no metadata attached.
|
||||
#
|
||||
my $pid;
|
||||
$pid = open2(*read_from, *write_to,
|
||||
"openssl rsautl -sign -inkey $private_key -keyform PEM") ||
|
||||
die "openssl rsautl";
|
||||
binmode write_to;
|
||||
print write_to $prologue . $digest || die "pipe to openssl rsautl";
|
||||
close(write_to) || die "pipe to openssl rsautl";
|
||||
|
||||
binmode read_from;
|
||||
read(read_from, $signature, 4096) || die "pipe from openssl rsautl";
|
||||
close(read_from) || die "pipe from openssl rsautl";
|
||||
waitpid($pid, 0) || die;
|
||||
die "openssl rsautl died: $?" if ($? >> 8);
|
||||
}
|
||||
$signature = pack("n", length($signature)) . $signature,
|
||||
|
||||
#
|
||||
# Build the signed binary
|
||||
#
|
||||
my $unsigned_module = read_file($module);
|
||||
|
||||
my $magic_number = "~Module signature appended~\n";
|
||||
|
||||
my $info = pack("CCCCCxxxN",
|
||||
$algo, $hash, $id_type,
|
||||
length($signers_name),
|
||||
length($key_identifier),
|
||||
length($signature));
|
||||
|
||||
if ($verbose) {
|
||||
print "Size of unsigned module: ", length($unsigned_module), "\n";
|
||||
print "Size of signer's name : ", length($signers_name), "\n";
|
||||
print "Size of key identifier : ", length($key_identifier), "\n";
|
||||
print "Size of signature : ", length($signature), "\n";
|
||||
print "Size of information : ", length($info), "\n";
|
||||
print "Size of magic number : ", length($magic_number), "\n";
|
||||
print "Signer's name : '", $signers_name, "'\n";
|
||||
print "Digest : $dgst\n";
|
||||
}
|
||||
|
||||
open(FD, ">$dest") || die $dest;
|
||||
binmode FD;
|
||||
print FD
|
||||
$unsigned_module,
|
||||
$signers_name,
|
||||
$key_identifier,
|
||||
$signature,
|
||||
$info,
|
||||
$magic_number
|
||||
;
|
||||
close FD || die $dest;
|
||||
|
||||
if (!$keep_orig) {
|
||||
rename($dest, $module) || die $module;
|
||||
}
|
||||
Loading…
Reference in New Issue
Block a user